Commented lines are duplicated if the last line is empty

[numToStr]

Steps

1. Create a lua file with these lines (last line should be empty)

local first = 123
local second = 456

2. Comment first two lines
3. Now select all three lines and comment them.

Expected

-- -- local first = 123
-- -- local second = 456
--

Actual

-- local first = 123-- -- local first = 123
-- local second = 456-- -- local second = 456
--